Disco '96 300TDi gearbox problems

[FlagonSlayer]

Hi all, great site!!

So..... it was Friday 13th (‘wot, me superstitious? – nah…’) and we’re 80 miles up the road in Rutland – just another 6 miles and the odometer will be rolling over to show 100k miles. All the way there, and all the way to Somerset and back the day before, she’s been running smooth as silk.

5 hours later (after a ‘quick’ stroll) start her up, reverse out of the parking space ..and then the trouble starts – take her out of reverse but then can’t get any gears at all. Try pumping the clutch (feels normal), keep trying the gear lever (suddenly very stiff and reluctant to move) - eventually get second gear and pull away gently but with an ‘orrible whirring sound from the ‘box at the same time.

Out of the car-park, 1/2 mile down the road, into 4th but then can’t get any gears again (up or down) so dip the clutch and pull over on the grass verge. No gears available but after several attempts manage to get out of 4th and into neutral (feels like stirring thick treacle). Start her up again, just about able to get gear stick to move to various positions but still not engaging (again a whirring sound until clutch pedal depressed, but no motion). By now I’ve checked clutch fluid (it’s full) and no obvious signs of oil leaks (none at the carpark either).

Finally manage to get into gear by going into difflock/high-range(??) move to a safe spot 20 yards down and reverse up a track off the road to wait for the AA. Two AA patrols reach same conclusion: ‘gearbox has probably had it - Discovery gearboxes are notorious’ (no kidding?).

80 miles on a flat-bed later…. arrive home, back her off the truck, into reverse (without difflock) – up off the road and onto the driveway. Take her out of reverse without any problem, gear lever seems to be shifting smoothly and without any whirring noises???

Tried her again today for the first time since: 100 yards down the road and back – gears shifting without any trouble, 1st through to 3rd and reverse, then home again (don’t push me luck!).

Can’t risk her on a run or for work again until problem is sorted (if it’s happened once….) – so has anyone got any thoughts as to what might be up wi’ ‘er please – i.e. just how bad is it?? :roll:

[suggs]

so sounds like it was ok when the engine was cool, but not when it was warm..

could be the gear oil getting hot and breaking down, i had a TD5 that after a long run up the motorway would be very stiff getting into gear for a little while, as you say like pushing the stick through thick treacle, i know that fitting an oil cooler can stop it on the TD5. the cooler is standered on export Discos to hot climates..

[FlagonSlayer]

It doesn't seem to be temperature related - it was fine at the end of a long journey, then wouldn't work after cooling down for 5 hours.  Trying it again today when it was cold though it seemed ok?

[suggs]

sorry miss read your post, though it happened at the end of an 80 mile drive..

[hobbit]

Would be worth doing an oil change and examining the old oil for any bits/colour and texture

[FlagonSlayer]

Yep, an oil change and inspection wouldn't do any harm I guess

[Budgie]

Remember it's ATF or MTF94 in the R380 gearbox.  

[stageonesimmo]

Sounds to me like the grub screw on the lower selector shaft has come adrift - happens a lot to the WOLF fleet at work - exactly the same symptoms.

Its a top off the box job   :shock:

i do hope I'm wrong though.................

[Disco-andy]

It could well be the cluch fork,  when mine went the cluch felt normal but was alwasys engaged. i used crunching in and out of tranferbox to get gears , wich got me off the motorway.  Hope its not as its a cheep part but lots of work. but if it feels like the cluch isn't braking the engin and boxes it may well be.

[FlagonSlayer]

Hmm sounds like I could be up the proverbial aromatic creek, sans paddle either way - methinks deep-pocket solutions are indicated   :(

[Budgie]

If it was the clutch fork then surly you wouldn't be able to drive it now?
I thought that once it's gone, it's gone. It wont come back and then go again.

Give it an oil change, see what the old stuff is like and see how it runs with the new oil in there before you go thinking about pulling the gearbox out.
If, when you drain the box, you find it's been running on EP90 instead of ATF/MTF then that could have damaged the internal oil pump as the EP90 is too thick for it.
Another thing to check is that the gearbox breather is clear. It could have been a build up of pressure in the box that's caused it because of the long run.

[FlagonSlayer]

Thanks Budgie - I've got my suspicions about the oil they put in at the last 'major' service some time ago - box started getting a bit stiff from time to time soon after but I put it down to new oil and cold time of year (seemed to loosen up a bit after a run).  The garage I use isn't a specialist LR place - just a 2-man outfit but I've known 'em for many years and they're a good honest  bunch.